Shell has won its appeal against a landmark climate judgment by a Dutch court, which in 2021 ordered the fossil fuel company to sharply reduce its greenhouse gas emissions.

A court of appeal ruled on Tuesday that, while Shell does have a “special responsibility” to cut its emissions as a big oil company, this would not be achieved by imposing a specific legal goal.

Shell had appealed against a lower court ruling in 2021 that it must cut its global carbon emissions by 45% by the end of 2030 compared with 2019 levels. It was the first such ruling against a company in the world.

Shell’s chief executive, Wael Sawan, welcomed the appeal decision, saying it was “the right one for the global energy transition, the Netherlands and our company”.

The case was brought by Milieudefensie, the Dutch arm of Friends of the Earth, and more than 17,000 co-plaintiffs.

“This hurts,” said the director of Milieudefensie, Donald Pols. “At the same time, we see that this case has ensured that major polluters are not immune and has further fuelled the debate about their responsibility in combating dangerous climate change. That is why we will continue to tackle major polluters, such as Shell.”

Shell was originally told it must slash emissions within its own operations, as well as those of its suppliers and buyers, in line with the Paris climate agreement.

During its appeal, Shell argued in court that corporate emissions were a matter for politicians, not the judiciary, and that any fossil fuels it chose not to extract would simply be exploited by another company.

The appeals court said Milieudefensie had the right to bring such a claim even though political choices must be made to combat dangerous climate change.

But it was not convinced that a reduction obligation imposed on a specific company would have the effect of limiting emissions from its customers, “especially if this reduction obligation can also be realised by selling less fossil fuels”.

Milieudefensie had accused Shell of failing to comply with the initial court ruling, which explicitly said the company should begin to act on the judgment immediately regardless of any appeal.

The NGO gave evidence to the court that, despite increasing its volume of renewables, Shell was also planning to develop hundreds of new oil and gas fields despite the International Energy Agency warning against investments in any new fossil fuel extraction.

The court said it was “reasonable to expect oil and gas companies to take into account the negative consequences of a further expansion of the supply of fossil fuels for the energy transition also when investing in the production of fossil fuels. Shell’s planned investments in new oil and gas fields may be at odds with this.”

However, it said this was not relevant to whether a specific reduction obligation should be imposed on the company.

Sawan said Shell still planned to halve emissions from its operations by 2030, adding: “We are making good progress in our strategy to deliver more value with less emissions.”

The court did uphold the statement that companies such as Shell had obligations to protect human rights.

The judgment can still be appealed against and taken to the supreme court. However, this would focus on interpretation of the law and not the key facts of the case.

Sjoukje van Oosterhout, head of research at Milieudefensie, said the NGO would read the full ruling carefully before deciding whether to appeal. But she said she believes there is still room for future legal action against corporations.

While this appeal was taking place, other domestic courts issued important rulings on assessment of greenhouse gas emissions from fossil fuel projects. In January 2024, Norway blocked the development of three North Sea oil and gas fields on the grounds that the state did not properly assess the impact of future use on climate breakdown. The UK supreme court issued a similar ruling several months later.

At a seaside restaurant near the docks in Fredrikstad, Norway, there’s a selection of delicious looking entrees sitting in front of me. There is a cheesy lasagne, a savoury Mexican casserole, and a spicy chilli con carne. Biting in to each one in turn, I savour the familiar taste of ground beef. Or is it?

The dishes come from Pronofa Asa, a Scandinavian company whose purpose is to make new and sustainable protein sources. In 2022, it acquired the Swedish research company Marine Taste and expanded on its work turning ciona – or “sea squirts” to you and me – into mincemeat. The dishes in Fredrikstad were prototypes, but Pronofa plans to have its mincemeat on supermarket shelves in Norway and Sweden before the end of the year, it says, and will aim to expand throughout Europe in the coming years.

Ciona is naturally rich in proteins, and can be used as an alternative feed for fish or animals as well as people.

“The sea squirt is the only organism that produces 100% pure cellulose,” says Hans Petter Olsen, the CEO of Pronofa. “So there are some fibres in the meat and we had to work on how to process them so the mouthfeel would be similar to meat.”

Pronofa, and a number of companies like it, are developing alternative protein sources for kitchen tables around the world, which have a minimal carbon footprint but that taste like family favourites. The Food Standards Agency said in October that cell-cultivated meat could be on sale in the UK within a few years. Cultivated chicken was approved for sale to consumers in Singapore in 2020 and in the US in 2023 and cultivated steak was approved in Israel in 2024. Scores of companies around the world are developing similar products, including using pork and fish.

Ciona are umami flavoured, but naturally have a slight seafood taste and a texture reminiscent of calamari. There are no additives – this transformation to “fake meat” is accomplished simply by the way that the company processes the sea squirt, says Olsen.

Changing the sea squirt into something that looks enticing is important as ciona does not look appetising. Burping and bubbling in the freezing waters of the North Sea, sea squirts are translucent tubes that resemble gelatinous sacs. They will grow on almost any solid surface in the sea, from rocks and driftwood to deliberately placed ropes.

They have two siphons on the top of their tubular bodies: one for pulling in nutrient-rich sea water, the other for expelling filtered water.

Yet, once processed, ciona can be consumed in surprisingly traditional recipes. “We had to work on how to eliminate the marine taste,” says Olsen. “Because it should not taste marine or fish-like at all. It is going to taste like meat.”

But sea squirts are more than just another alternative protein source. Farming ciona is “super-sustainable”, according to Olsen, in part because they require almost no input from the farmer. Ropes are seeded with ciona larvae, similar to farming oysters or mussels. The farmer’s labour is required at harvest time, when the long ropes covered in sea squirts are hauled from the ocean, the ciona removed, and then processed.

Often considered a highly invasive species, varieties of tunicates (of which ciona are just one) appear uninvited on ropes, buoys, bowlines and docks around the world. Most have potential for culinary uses, but Pronofa’s recipes are specially formulated for the ciona that thrive in the North Sea. In spite of being an invasive species, ciona and other tunicates can be of tremendous value to the environments they grow in, filtering out nitrogen from the ocean waters.

“One of the side effects of agriculture is the nitrogen surplus,” says Olsen, “Surplus that is running into the rivers and causing the algae to grow too much. But if you drive close to one of our tunicate farms, the ocean will be like the Mediterranean – crystal clear waters, and visibility of 30 metres.”

However, sea squirt farming is not without its difficulties. A venture to farm the variety haloceynthia roretzi, or sea pineapple, for human consumption in Korea has struggled to have any impact due to continued events of mass mortality. Scientists in Korea believe the die-offs are caused by a parasite whose destructive capabilities may be increased by the monoculture nature of tunicate farms.

Nevertheless, Pronofa hopes that its work with the invertebrates will turn it into a food staple rather than just another fashionable and short-lived meat alternative.

“For us, it is very important not to be put on the same shelf as Beyond Meat and all those other meat replacements,” says Olsen. “Eventually, we want to compete on scale with the salmon industry in Norway, and we want to deliver millions of tonnes of our products.” The Norwegian salmon industry makes up 2% of Norway’s GDP and is worth more than $10bn (£7.7bn) annually, according to the Norwegian Seafood Council.

Olsen’s bold vision starts with a plate of convincingly meat-like ciona mince, drenched in tomato sauce, cheese and sandwiched between sheets of pasta. It looks like meat, and one forkful confirms, it tastes like meat. Ciona mincemeat could be the next ground beef – without the environmentally destructive processes associated with cattle farming. But for now, it’s a case of watch this space.

Social media platform Bluesky has picked up more than 700,000 new users in the week since the US election, as users seek to escape misinformation and offensive posts on X.

The influx, largely from North America and the UK, has helped Bluesky reach 14.5 million users worldwide, up from 9 million in September, the company said.

Social media researcher Axel Bruns said the platform offered an alternative to X, formerly Twitter, including a more effective system for blocking or suspending problematic accounts and policing harmful behaviour.

“It’s become a refuge for people who want to have the kind of social media experience that Twitter used to provide, but without all the far-right activism, the misinformation, the hate speech, the bots and everything else,” he said.

“The more liberal kind of Twitter community has really now escaped from there and seems to have moved en masse to Bluesky.”

Bluesky began as a project inside Twitter but became an independent company in 2022, and is now primarily owned by chief executive Jay Graber.

The platform has previously benefited from dissatisfaction with X and its billionaire owner, Elon Musk, who is closely tied to US president-elect Donald Trump’s successful election campaign. Twitter shed millions of users after rebranding to X and usage in the US slumped by more than a fifth in the subsequent seven months.

Bluesky reported picking up 3 million new users in the week after X was suspended in Brazil in September and a further 1.2 million in the two days after X announced it would allow users to view posts from people who had blocked them.

“We’re excited to welcome all of these new people, ranging from Swifties to wrestlers to city planners,” Bluesky spokesperson Emily Liu said.

Ruth Ben-Ghiat, a historian and professor at New York University, had 250,000 followers on X but picked up 21,000 followers in her first day on Bluesky this week.

“I am still on X but after January, when X could be owned by a de facto member of the Trump administration, its functions as a Trump propaganda outlet and far-right radicalization machine could be accelerated,” she said.

Bluesky is still second to Threads in the social networking category on Apple’s US App Store, which reported reaching 275 million monthly active users in November, up from 200 million in August.

The independent platform has recently added features including direct messaging and video compatibility to more closely resemble X and distinguish itself from its Meta-owned competitor.

Ben-Ghiat has found the site’s “starter packs”, or groups of people with similar expertise and interest, a refreshing way in.

“[They] promise to give Bluesky some of what I valued on Twitter/X: informed takes on a subject from multiple points of view,” she said.

Bruns, a professor at Queensland University of Technology’s Digital Media Research Center, said the explosion in user numbers had created “growing pains” as new users learned to navigate the site but was ultimately adding to the site’s momentum.

“It really feels like a throwback to those days of the early excitement about social media in many ways, and that’s what, at the moment, attracts quite a few people,” he said. “It just makes it more vibrant, more active place.”

On Monday night, New York congresswoman Alexandria Ocasio-Cortez posted that she was “back” on Bluesky, saying “Good GOD it’s nice to be in a digital space with other real human beings.” Her post was liked by 27,000 people.

Days of severe storms have been forecast for every mainland state and territory in Australia this week, with possible wind gusts, heavy rain, large hail and flash flooding on the cards.

Weatherzone meteorologist Ben Domensino said “millions of lightning strikes” were also expected across the country.

“We have a number of low pressure troughs sitting over Australia that are interacting with very warm and humid air coming in from the oceans surrounding Australia, which are warmer than average for this time of year,” he said.

In Sydney, temperatures were forecast to remain in the mid-20s for the rest of the week and into the weekend. Melbourne could expect to reach 25C on Tuesday and 20C on Wednesday, warming up towards the weekend with temperatures in the 30s forecast for Saturday and Sunday.

But thunderstorms were forecast to continue across parts of New South Wales, south-east Queensland and central Australia on Tuesday, while northern and Western Australia were set to bear the brunt of low pressure troughs in the latter half of the week.

Dean Narramore, senior meteorologist with the Bureau of Meteorology, said Tasmania was the only state that may escape the wild weather.

“We’re just looking at days of severe storms across parts of the country, and particularly north-east New South Wales and south-east Queensland for the coming days, with Wednesday probably being the bigger day,” he said.

Severe thunderstorms could mean damaging wind gusts and heavy rain with the potential for flash flooding or large hail, he added.

There was also the potential for severe thunderstorms in central Australia – near the border of South Australia, Western Australia and the Northern Territory – with large hail, damaging winds and heavy rainfall likely, he said.

Meanwhile, in parts of northern Australia, severe to locally extreme heatwaves with 40C temperatures were forecast for Marble Bar in Western Australia throughout the week, expected to peak at 45C on Wednesday.

“We’ll start to see that ease as we head towards the weekend, at least for the Kimberley and the Top End,” Narramore said, though heatwave conditions were expected to continue around Cape York into the weekend.

The recent State of the Climate report, released by the bureau and CSIRO, said global heating caused by burning fossil fuels was fuelling warmer ocean temperatures and longer, more intense heatwaves.

The wreck of the long-lost US warship USS Edsall, sent to the bottom of the sea during the second world war by the Japanese, has been discovered, US and Australian officials announced on Monday.

The warship was sunk on 1 March 1942, three months after Japan’s attack on Pearl Harbor. The Edsall was traveling across the Indian Ocean south of Java when it was sunk by Japanese dive bombers.

The Edsall’s formidable display in evading attacks before its demise led the Japanese to dub the ship “the dancing mouse”.

“I am honored to acknowledge the role #AusNavy played in discovering the wreck of @usnavy USS Edsall, a warship that holds a special place in our shared naval histories,” wrote Caroline Kennedy, the US ambassador to Australia, in an Instagram post to commemorate Veterans Day.

“We will now be able to preserve this important memorial and hope that the families of the heroes who died there will know their loved ones rest in peace,” said Kennedy in an accompanying video.

The second world war ship, only about 300ft in length, was carrying 153 sailors and several dozen army air forces pilots and soldiers. It had sustained damage from an earlier attack and deemed unfit for combat but was deployed to aid another ship when it encountered Japanese naval forces at about 4pm.

Despite its damaged state, the Edsall successfully dodged attacks for over an hour, swerving to avoid the hundreds of fired shells. The Edsall counterattacked with a smokescreen and torpedoes before eventually being overcome by Japanese dive bombers.

Historians say that a few people on board survived the sinking ship but were immediately picked up by enemy forces and later beheaded in a prison camp.

According to the US navy, the wreck was first discovered late last year south of Australia’s remote Christmas Island submerged in 18,000ft of water. The US cooperated with Australian officials to confirm the wreck was in fact the Edsall.

Mark Hammond, chief of the Royal Australian Navy, said in the video that the wreck was found by the MV Stoker, an Australian naval support ship that is normally used for hydrographic surveying.

The wreckage was subsequently examined with underwater robots and sonar. The Australian navy has not disclosed what the Stoker was doing when the Edsall was found, citing “operational security sensitivities”, according to the Washington Post.

Donald Trump has picked Lee Zeldin, a former New York congressman, to lead the Environmental Protection Agency (EPA), vowing the appointment will “ensure fair and swift deregulatory decisions” by the regulator.

Trump, who oversaw the rollback of more than 100 environmental rules when he last was US president, said that Zeldin was a “true fighter for America First policies” and that “he will ensure fair and swift deregulatory decisions that will be enacted in a way to unleash the power of American businesses, while at the same time maintaining the highest environmental standards, including the cleanest air and water on the planet”.

Zeldin, a Republican who was in the House of Representatives until last year as a member for a New York district that covers part of Long Island, said the nomination was an “honor” and that he was looking forward to cutting red tape as the EPA administrator.

“We will restore US energy dominance, revitalize our auto industry to bring back American jobs, and make the US the global leader of AI,” Zeldin wrote on X. “We will do so while protecting access to clean air and water.”

Zeldin, 44, is considered a close Trump ally and ran in a surprisingly close race for New York governor in 2022, before being pipped by Kathy Hochul, a Democrat. During the campaign, Zeldin attacked Hochul’s “far-left climate agenda” and assailed Democrats for allegedly forcing people to drive electric cars.

The EPA nominee, who will have to be confirmed by the US Senate, has rarely spoken out on environmental or climate issues, although he said in 2014 he was “not sold yet on the whole argument that we have as serious a problem as other people are” with global heating, and added in 2018 that he did not support the Paris climate agreement, which Trump is again expected to withdraw the US from.

Zeldin, who has a score of just 14% from the League of Conservation Voters on his votes on environmental issues in his 15 years in Congress, is expected to oversee an overhaul of the EPA that will rival anything seen since its foundation in 1970.

An exodus of staff is expected from the agency, with employees already raising fears they will be subject to political interference and that their work to protect Americans from toxic chemicals and planet-heating emissions from cars, trucks and power plants will be torn up.

“Naming an unqualified, anti-American worker who opposes efforts to safeguard our clean air and water lays bare Donald Trump’s intentions to, once again, sell our health, our communities, our jobs, and our future out to corporate polluters,” Ben Jealous, executive director of the Sierra Club, said of Zeldin’s nomination.

“Our lives, our livelihoods, and our collective future cannot afford Lee Zeldin – or anyone who seeks to carry out a mission antithetical to the EPA’s mission.”

The naming of Zeldin, less than a week after Trump won the presidential election, is far quicker than his previous term in the White House, when he took until December to name Scott Pruitt as his pick for the EPA.

Pruitt resigned in 2018 amid a flurry of ethics scandals, including allegations that he gave staffers improper pay raises, that he constructed an expensive soundproof phone booth in his office, and that he tasked employees with fetching him moisturizer and a favorite mattress.

Keir Starmer will announce a stringent new climate goal for the UK on Tuesday, the Guardian can reveal, with a target in line with the advice given to the government by its scientists and independent advisers.

The UK will pledge to cut emissions by 81% compared with 1990 levels by 2035, a target in line with the recommendations of the Climate Change Committee.

The goal will be one of the first national plans on cutting carbon, known as “nationally determined contributions” or NDCs in UN jargon, to be unveiled at Cop29, the crucial UN climate summit taking place in Azerbaijan this week, and is expected to be one of the most ambitious of any government at the talks.

The goal would be achieved by decarbonising the power sector and through a massive expansion of offshore wind, as well as through investments in carbon capture and storage and nuclear energy.

The UK is one of the first countries to announce an NDC, which are not due until February next year. Campaigners have found the NDCs submitted so far “underwhelming”. The NDC submitted by the previous Cop host, the United Arab Emirates, was described as “greenwashing” by 350.org. A submission by the next host, Brazil, was also criticised for being insufficient and called “misaligned” by Climate Observatory.

Friends of the Earth’s head of campaigns, Rosie Downes, said: “With the warning signals flashing red, a planet battered by increasingly severe floods, storms and heatwaves, and the election of climate denier President Trump, the need for climate leadership by the UK has never been more urgent. Starmer’s 2035 carbon-reduction pledge is a step in the right direction but must be seen as a floor to the level of ambition, not a ceiling. Deeper, faster cuts are needed to help avert the climate collision course we are on.

“Furthermore, if these targets are to be credible, they must be backed by a clear plan to ensure they are met. The UK’s existing 2030 commitment is currently way off course.”

On Monday, the World Meteorological Organization followed the EU space programme in saying 2024 was on track to become the hottest year on record.

Few big countries have yet come up with NDCs. The Cop29 talks opened on Monday, but will ratchet up a gear on Tuesday when scores of heads of state and government fly in from around the world.

Giorgia Meloni, the prime minister of Italy, Recep Tayyip Erdoğan, the president of Turkey and Mohammed bin Salman, the crown prince of Saudi Arabia, are among the other leaders attending. Joe Biden of the US, Xi Jinping of China, Olaf Scholz of Germany and Emmanuel Macron of France will not be at the talks, with the latter two preoccupied by domestic political crises.

On Monday, delegates heard stark warnings from the UN climate chief, Simon Stiell, and the Cop president and Azerbaijani environment minister, Mukhtar Babayev, urging countries to step up with strong commitments on the climate before it is too late.

This summit, at which nearly 200 countries are expected to be represented, will focus on climate finance – ways of getting poor countries access to the money they need to cut their greenhouse gas emissions and adapt to the impacts of extreme weather.

About $1tn (£780bn) is expected to be needed each year by 2035, but developed countries have agreed to ensure only $100bn a year from public funds.

The host country claimed an early win in the talks by signing off on a deal intended to make carbon offsets work for the planet, and as a source of cash for poor countries.

Diplomats have given the green light to rules that govern the trade of “carbon credits”, breaking a deadlock that has lasted years and paving the way for rich countries to pay for cheap climate action abroad while delaying expensive emission cuts at home. But critics warned the rules were rushed through without following proper process.

Carbon offsets, or carbon credits, are awarded to countries with large forests that absorb carbon dioxide from the atmosphere, or to projects that reduce greenhouse gas emissions, such as wind or solar farms. Selling them should be a source of cash for the developing world, but years of argument over how exactly such a system would work have prevented the widespread uptake of trading systems.

The beginnings of a potential system for trading were set out in article 6 of the Paris climate agreement in 2015, but countries have struggled to put the idea into practice, owing to disagreements over technical issues, such as how to avoid double counting, and ideological differences, as some countries are wary of using carbon offsets.

Azerbaijan hopes the progress on article 6 will clear the way for more substantive talks, for the rest of the scheduled fortnight, on a goal of making $1tn a year in climate finance available to poorer countries by 2035.

However, many civil society groups remain concerned about article 6. Erika Lennon, an attorney at the Center for International Environmental Law, said: “We’ve seen over and over again how carbon markets are not doing what they claim to be doing, as well as market projects that violate people’s rights. If they don’t have strong rules in place to prevent all of the abuses, it can totally undermine the integrity of the Paris agreement.”

Diplomats have greenlit key rules that govern the trade of “carbon credits”, breaking a years-long deadlock and paving the way for rich countries to pay for cheap climate action abroad while delaying expensive emission cuts at home.

The agreement, reached late on the first day of Cop29 in Azerbaijan, was hailed by the hosts as an early win at climate talks that have been snubbed by prominent world leaders and clouded by the threat of a US retreat from climate diplomacy after Donald Trump’s victory in the presidential election.

But critics have warned the rules were rushed through without following proper process.

“We welcome this positive momentum,” said Mukhtar Babayev, the president of Cop29, praising a “spirit of compromise that I hope will inspire all our work here in Baku”.

The rules deal with some of the final hurdles to creating a system in which countries can buy credits for removing or avoiding planet-heating pollution in other parts of the world – for instance, by planting trees or saving rainforests – and count the progress toward their own emissions targets.

The agreement is expected to provide the clarity needed to trade emissions within a global carbon market, supervised by the UN, that would be open to companies as well as countries. A separate article on the trade of carbon credits between individual nations will be addressed later in the Cop29 negotiations.

Carbon markets are a polarising force in climate policy. Supporters say they help direct crucial funds to saving the planet while critics point to the tattered history of fraudulent and harmful projects – particularly in the voluntary carbon market that some companies have enthusiastically embraced – that have eroded trust in the concept and driven calls for stricter rules.

Efforts to agree on carbon market rules – known in Cop jargon as article 6 – have been a persistent stumbling block in UN talks to stop the planet from heating. Diplomats at the last climate talks rejected proposals from a UN supervisory body that was tasked with recommending solutions for countries to debate.

This year, with pressure to make progress on carbon markets riding high, the group took a different approach, and adopted new standards on methods and removals while recommending the Cop29 negotiators give it the green light.

Isa Mulder, a policy expert at the nonprofit group Carbon Market Watch, said that adopting the rules on the first day of the summit without discussion “undermined trust” in the UN climate conference process. “Kicking off Cop29 with a backdoor deal … sets a poor precedent for transparency and proper governance,” she said.

The rules are expected to reduce the risk of double-counting emissions – a big concern of critics – and include stronger safeguards to protect human rights.

But the text also leaves many unanswered questions, said Mulder, such as how to deal with projects whose carbon-saving successes face a risk of reversal.

Olga Gassan-zade, a former chair of the article 6 supervisory body and one of its current members, said: “The criticisms of the process are fair – but it was also critically important to operationalise article 6.4 as soon as possible to scale up the delivery of carbon finance to the developing world.”

Critics of carbon markets have pointed to a history of offset projects overpromising and underdelivering, with wildfires burning through forests that were supposed to be protected and emissions from renewable energy projects being counted on balance books even though they would probably have been built anyway.

Erika Lennon, an attorney at the Centre for International Environmental Law, said: “We’ve seen over and over again how carbon markets are not doing what they claim to be doing, as well as market projects that violate people’s rights.

“If they don’t have strong rules in place to prevent all of the abuses, it can totally undermine the integrity of the Paris agreement.”

Using LED lighting on the underside of surfboards or kayaks could deter great white shark attacks, new research suggests.

In an Australian-led study using seal-shaped decoys, underside lighting disrupted the ability of great whites to see silhouettes against the sunlight above, reducing the rates at which the sharks followed and attacked the artificial prey. The brighter the lights, the more effective the deterrent was.

The study’s lead author, Dr Laura Ryan of Macquarie University in Sydney, said white sharks seemed to rely on the visual cues of a dark object silhouetted against a lighter background.

“If you flip that to a light object on a dark background, then it doesn’t seem to be something they recognise as prey,” she said.

Ryan’s previous research on great whites suggests that attacks on humans may be a case of mistaken identity. The animal has a far lower visual acuity – the ability to see shapes and details – than humans.

Her work has suggested that juvenile great white sharks, from below, are unlikely to be able to clearly tell seals apart from swimmers or people paddling surfboards.

Other research has shown that sharks are colour-blind or at best have only limited colour perception abilities.

The new study, conducted in Mossel Bay, South Africa, involved towing decoys behind a boat for dozens of hours.

The researchers initially found success by covering the underside of the decoy entirely in lights. “But if you’re actually going to come up with something to protect people, [entirely] covering a surfboard … is just not practical because it’s a huge amount of lighting, which needs a huge amount of battery power,” Ryan said.

The researchers experimented with more sparse lighting options, finding that horizontal stripes of LED lights had a similar deterrent effect. “When you do horizontal stripes, the silhouette [appears] wider than it is long, so it’s less like a seal,” Ryan said.

Longitudinal strips of light, however, were not effective, nor were strobe lights, which gave the sharks momentary glimpses of the decoy silhouette. “Interestingly, just that small glimpse of the entire silhouette was enough for the white sharks to start biting the decoys,” Ryan said.

The scientists towed the seal decoy to encourage the white sharks to breach – one form of hunting involving rapid acceleration to the surface to catch prey. They say more research is required into shark behaviour with static decoys, which would resemble surfers waiting to catch a wave rather than actively paddling.

The team is currently testing a surfboard prototype with fitted lighting. “Surfers can be a little bit fussy with their surfboards,” Ryan said. “As a surfer, I want it to be useable.”

Globally, most shark bites are associated with people surfing or participating in other board sports. Fatal shark bites, though rare, are mostly due to great whites.

The study, published in the journal Current Biology, noted it would be important to test whether lighting was also effective in deterring other species involved in attacks on humans, such as bull sharks and tiger sharks, as these have different predation behaviours.

You’ve likely already heard the worst-case takes: that a second Trump presidency is a disaster for the climate, and will almost certainly lead to emissions being higher than they otherwise would have been. There’s obvious truth in that. But it’s also true that Trump 2.0 will almost certainly not play out in line with immediate post-election predictions.

We have been here before. As the writer and analyst Ketan Joshi points out, in 2016 it was projected that Trump’s policies would lead to a steep rise in US emissions – a fork in the road at odds with the decline forecast if Hillary Clinton had won.

In reality, the country’s climate-heating pollution over the past eight years has been roughly what was predicted if the Democrats had been in the White House. There have been a bunch of reasons for this.

Most obviously, Trump promised to bring coal power back but failed, spectacularly. Coal-fired generation fell nearly 40% during his first term as investors and markets abandoned it as a viable, affordable energy source. States and cities ramped up climate action in response to Trump’s rise and private capital began to respond to the signal from the landmark 2015 Paris agreement even as the US pulled out of that deal.

Of course, the pandemic also dented emissions once shutdowns kicked in. But the rebound as the economy reopened did not take US emissions back to where they were before. The most recent data has it slightly below the 2016 projection of life under a Clinton presidency.

Looking ahead, there are a few things we can say.

Trump will again withdraw the US from the Paris agreement, and possibly the overarching UN Framework Convention on Climate Change. At least some of the extraordinary US$370bn (A$560bn) clean energy support in the Inflation Reduction Act is quite likely to be rolled back even though it is driving investment in Republican states – logic is not necessarily a winner here. The US is highly unlikely to meet the 2030 emissions reduction target (a 52% cut below 2005 levels). And the election result will shape what happens at the fortnight-long Cop29 climate summit that began in Azerbaijan overnight.

Beyond that, there is much more we don’t know. Trump wants the country to “drill, baby, drill”, including in Alaska’s Arctic wilderness, but it is unclear what this will mean in practice. Fossil fuel extraction in the US already reached record levels under the Biden administration, much of it for export, before approval of liquified natural gas developments was paused this year. Support for clean energy will survive just because it makes clear economic sense, but it will be a while before the scale is clear.

What we do know is that the most consequential decisions affecting the climate over the next four years will not be made in Washington.

It was already true, but more than ever the most important gauges of climate progress will be what happens in China – easily the world’s largest polluter due to its extraordinary population, rising middle class and role as the globe’s main manufacturer – and how, where and when global investors deploy trillions of dollars in capital.

As always, the Chinese story on the climate crisis is mixed. According to an analysis by Lauri Myllyvirta, a respected China analyst from Finnish thinktank the Centre for Research on Energy and Clean Air, the country’s domestic emissions have flatlined over the past two quarters, leaving open a slight possibility they could fall this year.

If that happens, it will be a significant moment and ahead of schedule – China’s global commitment is that its climate pollution will peak before 2030 on the way to net zero before 2060. But it will need to do much more to play its part in staving off the worst effects of global heating.

China continues to go big on solar power, having installed 163 gigawatts of new solar (more than twice Australia’s entire electricity capacity) in the first nine months of this year alone. Its solar and wind generation are up 44% and 24% compared with a year ago, respectively. Nuclear power played a smaller role, creeping up only 4%.

After falling for months, its coal and gas-fired generation also rose by smaller amounts in the third quarter as record temperatures prompted people to reach for their air conditioners and ramp up electricity use. But emissions from steel, cement and oil were down as construction activity continued to drop.

The bottom line is that China is easily the world’s biggest driver of renewable energy – it has more than a third of the global capacity – while it also continues pursuing fossil fuel interests. Delegates at the Cop29 talks are watching for signs of whether it will respond to Trump’s return by taking a more aggressive leadership role on climate – not to save the planet, but to advance its strategic interests.

On the question of global investment in non-fossil fuel energy: it has grown dramatically over the past five years, increasing by nearly two-thirds, and is forecast to reach US$2tn this year. Most of the spending is on renewable power and energy efficiency, with support for energy grids and storage making up a smaller chunk and nuclear a much smaller piece again.

The solar and wind component, in particular, will need to continue to expand to meet a global goal of tripling renewable energy capacity by 2030. A potential side effect if Trump delivers on his promise to scrap the huge tax and production credits for clean energy in the Inflation Reduction Act may be that it increases competition between other countries, including Australia, to attract green spending.

All of this hangs over Cop29, where the main focus will be negotiations over a climate finance goal to help the developing world – and how to avoid backsliding on last year’s agreement that the world needs to transition away from fossil fuels.

Unpromisingly, the talks are being held in a petrostate, and the Azerbaijan deputy energy minister has been caught agreeing to help set up fossil fuel deals during the summit. Combined with events in the US, it is the sort of news that can make a cynic of even the most optimistic observers.

My advice? Don’t ignore it, but remember it is not the whole story.

The climate crisis is happening and will get worse, but the drive to limit it and clean up economies continues. There are areas where headway is being made. Just don’t expect it to be a straight line.